chore(release): 0.8.1 — duplicate adopt/open fix + fuzz harness bookkeeping

- version 0.8.0 -> 0.8.1 (bug-fix release; semver-checks 196 pass vs 0.8.0)
- CHANGELOG 0.8.1: the manager_routing-found duplicate adopt/open fix,
  the fuzz harness, and the verification summary
- publish exclude gains docs/research/ (internal research notes;
  fuzz/ was already excluded — package verified clean of both)
- fuzzing.md §7.9: standing no-hosted-CI policy — corpus replay is the
  release-verification fuzz gate; campaigns manual via the detached
  runner; OSS-Fuzz out; no workflow files in this repo
- AGENTS.md: corpus replay added to the verification checklist
- lockfiles: alkcall 0.8.1 (root + fuzz)

Verification: 684 tests; clippy -D warnings (main, wasm, fuzz/shared);
fmt clean; doc clean; wasm32-unknown-unknown check+clippy clean;
semver-checks 196 pass; publish --dry-run 116 files (no fuzz/research/
reviews/sdd/AGENTS in the tarball); fuzz corpus replay 5/5 green

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "alkcall"
-version = "0.8.0"
+version = "0.8.1"
 edition = "2021"
 rust-version = "1.88"
 license = "MIT OR Apache-2.0"
@@ -9,7 +9,7 @@ readme = "README.md"
 repository = "https://git.alk.dev/alkdev/alkcall"
 keywords = ["rpc", "json-rpc", "multiplexing", "wire-format", "alpn"]
 categories = ["network-programming", "asynchronous", "encoding"]
-exclude = [".opencode/", "AGENTS.md", "docs/reviews/", "docs/sdd_process.md", "fuzz/"]
+exclude = [".opencode/", "AGENTS.md", "docs/reviews/", "docs/sdd_process.md", "docs/research/", "fuzz/"]
 
 [workspace]
 members = ["."]